Do you mean (a) the writer of the book of Acts that contains Acts 4:10,12, or (b) the person who spoke those words in Acts 4 (Peter)? Evangelical Christians commonly distinguish the two. Below I give a brief summary of both from a typical evangelical perspective.

1) Author of the book (the writer who recorded Acts 4:10,12)
– Traditional and mainstream evangelical view: Luke wrote both the Gospel of Luke and the Acts of the Apostles. Luke is not viewed as an eyewitness of Jesus’ ministry but as a careful historian who compiled eyewitness testimony (Luke 1:1–4).
– Who was Luke? Luke is commonly identified as “the beloved physician” mentioned by Paul (Colossians 4:14) and as a traveling companion of Paul (the “we” sections in Acts, and references in Philemon and 2 Timothy). He was likely a Gentile (not of the Twelve).
– Internal and external evidence: The literary style and theology unify Luke and Acts. Early church fathers (Irenaeus, Tertullian, Origen, Eusebius) attribute Luke as the author. The “we” passages in Acts suggest Luke was with Paul for parts of the narrative.
– Date: Evangelical scholars often prefer an early date (before AD 70, many suggest around AD 58–62) because Acts does not mention the destruction of Jerusalem and because of the close connection to Paul’s life. Some place it later (70s–90s), but many conservative scholars favor the earlier range.
– Purpose and character: Luke states his intent to give an “orderly account” to Theophilus; Acts emphasizes the work of the Holy Spirit, the growth of the church, and continuity between Jesus’ mission and the apostles’ witness. Evangelicals highlight Luke’s careful historical method and confidence in the historicity of the events he records.

2) The speaker of Acts 4:10,12
– Those verses come from Peter’s speech before the Sanhedrin after he and John healed a lame man (Acts 3–4). So, while Luke recorded the words, the content is apostolic proclamation by Peter.
– Peter’s role: Peter is one of the Twelve apostles, an eyewitness of Jesus’ ministry, death, and resurrection. Evangelicals regard Peter’s preaching in Acts as authoritative apostolic testimony that the early church relied upon.
– Significance of Acts 4:10,12 (in context): Peter asserts that the healed man was healed by faith in the name of Jesus Christ, whom the Jewish leaders had crucified and whom God raised — and he declares there is salvation in no one else. Evangelicals see this as a clear early proclamation of the uniqueness of Christ for salvation and as evidence of the apostolic conviction and boldness.

If you’d like, I can:
– Quote the exact wording of Acts 4:10 and 4:12, or
– Give scholarly references (evangelical commentators like F. F. Bruce, Leon Morris, Craig Keener, Darrell Bock) that discuss Luke’s authorship and dating, or
– Summarize how evangelicals use these texts in preaching and doctrine.